4.1 Work

Energy is the ability to do work!
Work is done whenever there is a change or transfer of energy

Work : ( mechanical work)


Direction as the displacement

W= F . d ( dot product of the force and displacement vectors)

Product of the magnitude of the force and the magnitude of the displacement in the direction of the force

W = /F/ /d/ cos

F – magnitude of the force /F/
d – magnitude of the displacement
L - angle between the F and d
W – work done…….W is scalar

Units – W = /F/ /d/ cos
= [N] [m]
= N.M

1N.M = 1 Joule
=1 J
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